The invention relates to a fixing agent and a method for fixing an object on a base.
Attaching objects to the walls of buildings and the like represents a specific area of application where the method and/or the fixing agent in question can be used. In particular the walls of sanitary and kitchen areas are provided with wall coverings consisting of ceramic tiles or other tiles, or of stone and marble plates. The method generally relates to very different areas of application, such as the areas of airplane construction, ship construction and steel construction.
To attach equipment items such as furniture, lamps, sanitary equipment pieces in the form of towel holders or the like to these types of walls, fixing agents such as screws can in particular be used in a manner known per se. However, these fixing agents require that holes to be drilled into the walls, into which dowels must also be inserted. To prevent damage to very expensive wall coverings such as the ceramic tiles and other tiles, these holes are normally inserted into the joints between the tiles, thereby restricting in an undesirable manner the location for the fixing agents. A further disadvantage is that if the location where an equipment item is attached must be changed after a period of time, the holes inserted at the previous locations are visibly exposed, thereby considerably detracting from the total optical impression of the wall, even if the holes are subsequently filled with a filler material. To avoid these disadvantages, attempts have been made to replace fixing agents in the form of screws with adhesive agents.
In the simplest case, adhesive strips can be used which, for this very simple case, can also mean a double-sided adhesive tape. On the one hand, fixing agents of this type have the disadvantage that they can detach themselves again over time, wherein it is a further disadvantage that heavy equipment items cannot be attached to the walls with said strips or tape.
Also conceivable in principle is the use of aerobic adhesive as a fixing agent for securing objects on bases, such as the walls of a room in a building. One problem, however, is that aerobic adhesives of this type require several hours to harden, wherein it is necessary to supply liquid to the aerobic adhesive. However, if a layer of aerobic adhesive is applied to an object and the object is then pressed with the layer of aerobic adhesive against the base, the layer between the base and the object is cut off from the ambient air, so that a hardening of the aerobic adhesive is no longer possible.
A mounting system which permits the use of an aerobic adhesive of this type is known from the International Patent Application Publication No. WO 03/036106.
This mounting system is used for locally attaching objects such as towel holders, shelves, lamps or similar equipment items to a wall, a ceiling or the like, in particular to a surface covered with ceramic and other tiles or marble plates or to the wall surfaces of rooms provided with similar wall coverings. The mounting system consists of different types of fastening elements and an adhesive and joining agent which can be an aerobic adhesive. The fastening elements are made of sintered metals for which the shape must be adapted, depending on the use. The disadvantage of these systems is that they require very long hardening times for the adhesive, which can take up to twelve hours, wherein this strongly impairs the user friendliness of the mounting system.
The fastening element is used to accommodate an element for holding the object and consists of a basic body provided with a receptacle on the back side which is facing the wall, as well as a filling opening which empties into the latter and is used for inserting the adhesive and/or joining agent into the space between the fastening element and the wall.
The fastening element is provided with at least one liquid-permeable and gas-permeable opening to allow air to escape which is displaced by the adhesive and/or fixing agent inserted into the receptacle, wherein this opening extends from the receptacle to a different surface of the fastening element and accommodates the excess adhesive and/or joining agent.
The back side of the basic body which faces the wall is liquid-permeable and gas-permeable, at least in partial regions thereof, such that the gas developing during the hardening of the adhesive and joining agent in the receptacle can escape and/or that the volatile binding agent can evaporate and, at the same time, ambient air can reach this adhesive and joining agent, thus allowing it to harden and ensuring a stable, stress-resistant attachment of the fixing agent on the wall.
The disadvantage in this case, however, is that the shaping of the basic body requires considerable additional structural expenditure and, in particular, also restricts an optional embodiment of the fixing agent.
A fixing agent is known from German patent document DE 10 2009 023 285 which is composed of a mixture of aerobic adhesive and hydrophilic material.
By adding the hydrophilic material to the aerobic adhesive, a mixture is obtained which forms the fixing agent and which no longer requires surface contact with moist ambient air so that it can harden from the surface out. Rather, the hydrophilic material in the mixture, which is interspersed in the aerobic adhesive, ensures that the aerobic adhesive contained in the mixture can harden from the inside out even if there is no longer any contact with ambient air containing the moisture, meaning if the mixture is surrounded on all sides by diffusion-tight surfaces. The moisture needed for the hardening and/or the required oxygen is present in the hydrophilic material itself because its hydrophilic characteristics ensure that it contains sufficient moisture to meet the conditions necessary for the hardening of the aerobic adhesive in the mixture forming the fixing agent.
Since the hydrophilic materials release their moisture to the environment, depending on the environmental conditions, or also absorb moisture from the environment, the moisture content of the hydrophilic material may not be sufficient, depending on the application case, to ensure a complete hardening of the mixture once it is mixed with the aerobic adhesive.
The amount of moisture in the hydrophilic material and/or in the mixture of hydrophilic material and aerobic adhesive, however, is extremely important. Too much moisture destroys the adhesive bond while too little moisture does not result in a reaction in the aerobic adhesive which in particular is composed of polymers, so that no hardening occurs.
To obtain a suitable degree of moisture in the fixing agent DE 10 2009 023 285 discloses that moisture is metered into the mixture of aerobic adhesive and hydrophilic material. In particular, this involves a metered adding of moisture to the hydrophilic material before it is mixed with the aerobic adhesive.
A wooden spatula which is used to mix together the components is particularly suitable for metering in a liquid, wherein this spatula is first submerged in water or generally in an amount of liquid. The amount of water or in general the amount of liquid which can be absorbed by the spatula forms a metered amount of liquid which is supplied to the mixture of aerobic adhesive and hydrophilic material. The hydrophilic material in this case can function as moisture buffer which absorbs excess moisture and releases it again as needed. Owing to the mixing operation, the moisture is mixed into the complete volume, thereby allowing the mixture to harden completely. Alternatively to a spatula, other metering devices can also be used for supplying the liquid, wherein the use of encapsulated elements which contain liquid is in principle also possible. These elements burst open during the mixing operation and thus release the liquid into the mixture. In the same way as mixing in the hydrophilic material, the adding of the capsules makes it possible to improve the tensile strength and the shearing strength of the fixing agent, wherein it is possible in principle to add storage granules to the hydrophilic material for supplying the moisture.
As a result of the mixing with the hydrophilic material, the hardening takes place considerably faster than with all other methods.
The fixing agent thus allows attaching objects simply by inserting a layer of the fixing agent between the two objects.
The layer of fixing agent can thus be inserted into optional receptacles or holes in the objects and, once these objects are joined, can be located inside a completely enclosed space that is isolated from the ambient air, meaning a space delimited by diffusion-tight surfaces, wherein a secure hardening of the aerobic adhesive is nevertheless ensured and thus also a connection between the objects which can be subjected to high stress forces. The fixing agent can furthermore also be applied to flat surfaces. The fixing agent can therefore be used between two diffusion-tight surfaces in order to join these surfaces.
The composition of the aerobic adhesive in the form of silane-modified (MS) polymers is described in DE 10 2009 023 285.
As explained further in DE 10 2009 023 285, the hydrophilic materials can be salts. Alternative hydrophilic materials are hydrophilic carrier fibers, which can be natural fibers or synthetic fibers and which preferably are cotton fibers. In principle, substances such as chalk, flour, expanded clay, galactose, cotton wool, flax, hemp, viscose, cellulose, sea grass, felt or also wood fibers, air-entraining filters or breathable materials in general are suitable for use as hydrophilic materials.
One essential advantage of the fixing agent, described in DE 10 2009 023 295, is that a precise mixing ratio of aerobic adhesive and hydrophilic material need not be maintained to ensure the function according to the invention of the fixing agent. To ensure the best possible hardening of the aerobic adhesive, it is simply advantageous if the hydrophilic material is mixed as homogeneously as possible with the aerobic adhesive.
For the use of the fixing agent, it is furthermore essential that the components of the fixing agent are mixed together just prior to the use of the fixing agent.
An assembly kit is usefully provided for this which comprises two receptacles for the separate storage of the aerobic adhesive and the hydrophilic material, especially the hydrophilic carrier fiber. The desired amounts of the components can then be removed from these storage areas for mixing together the fixing agent.
The components of the fixing agent can be mixed together quickly and easily even by untrained personnel since no precise mixing ratios must be observed for the aerobic adhesive and the hydrophilic material.
A further advantage of the fixing agent is that it allows creating a reversible connection between two objects. This is based on the fact that the connection between the objects is extremely resistant to tensile forces acting upon the connection, but is less resistant to shearing forces acting upon it. The connection created with the fixing agent can thus be detached again by rotating an object. Residual amounts of fixing agent can subsequently be removed from the connecting locations with the aid of a spatula or the like.
According to the method disclosed in DE 10 2009 023 285, an object is affixed to a base with the aid of the following method steps:
For preparing the fixing agent, the hydrophilic material and in particular the hydrophilic carrier fibers must first be mixed together with the aerobic adhesive. Following this, a layer of fixing agent is applied to the object and the object is then affixed to the base by pressing the layer of fixing agent against the base. The aerobic adhesive in this layer then hardens as a result of the moisture contained in the hydrophilic material.
The liquid may be metered into the hydrophilic material prior to mixing together the aerobic adhesive and the hydrophilic material.
The aerobic adhesive and the hydrophilic material in particular are mixed together. Prior to that, the hydrophilic material is dried to prevent the hydrophilic material in the mixture from reacting with the aerobic adhesive. Moisture is then supplied to the mixture when preparing the fixing agent.
The hydrophilic material may be dried at least to approximately 0% humidity in the air before being mixed with the aerobic adhesive.
One advantage of this variant is that the mixture of aerobic adhesive and dried hydrophilic material can also be stored over a longer period of time since the hydrophilic material does not contain any moisture which would lead to a reaction with the aerobic adhesive and would thus result in the fixing agent.
The mixture in the form of a ready-to-use mixture can be filled into suitable containers and supplied to the clients who must only add liquid or moisture, in particular in the form of water, to produce the fixing agent.
The mixture is advantageously produced by adding dry hydrophilic material to the aerobic adhesive, maximally until the adhesive no longer absorbs hydrophilic material.
Observing this mixing ratio can be controlled simply by visually determining how long the aerobic adhesive can still absorb hydrophilic material which is added to the mixture.
According to one embodiment, a cartridge with 2 chambers is used for preparing the fixing agent, wherein one chamber is filled with the mixture of aerobic adhesive and dried hydrophilic material and the other chamber is filled with liquid, in particular water. The mixture and the liquid exiting the chambers are then mixed together with the aid of a mixing nozzle.
The 2-chamber cartridge is extremely easy to handle and has a compact structural configuration.
It is furthermore advantageous that following the mixing of the fixing agent, the residual amount of the mixture of aerobic adhesive and dried hydrophilic material which may still be inside the chamber can be used later on and can also be stored inside the cartridge chamber for longer periods of time.
According to one alternative embodiment, the mixture composed of aerobic adhesive and dried hydrophilic material is brought in contact with an object containing moisture.
This variant makes use of the circumstance that even small amounts of liquid, for example moisture contained in a wooden component, will be sufficient to allow the mixture of aerobic adhesive and hydrophilic material to react and form the fixing agent and/or to allow the fixing agent to harden.
It is particularly advantageous if the base is a wall and the object is a fastening element on which an equipment item can be affixed.
For this, the equipment item is attached to the fastening element once the layer of fixing agent between the wall and the fastening element has hardened. In general, however, equipment items can also be attached directly to the wall with the aid of the fixing agent.
The fastening element is generally attached to the wall without the use of screws and the like, so that no holes must be drilled into the wall.
As a result, an attachment can be accomplished without damage to or impairment of the wall.
This is particularly advantageous if the wall is provided with tiles or a similar wall covering, or is covered with stone or marble plates to which the fastening element is attached.
The sensitive and typically high-quality wall covering consequently is not in danger of being damaged or impaired during the attachment process.